Bad Rechargeable AA Batteries or Charger (1 Viewer)

Has anyone experienced any problems with Rechargeable AA Batteries for cameras?

I bought an Energiser 1 hour "rapid" charger, and I think it might over-charge the batteries or damage them.

Charged Batteries put in the charger indicate Reversed Polarity (indicator light blinks).
Also the camera (Canon 720is) won't accept them. Although I can put them in a torch or my mouse and they work fine.
Additionally the batteries get very hot (too hot to hold). Blurb says there is a therrmal cut out at 60 deg C.


(Not sure where to post this, feel free to move it if it is in the wrong place)

you'd expect your batteries to get hot if you want to charge them in 1hour 1 hour chargers seem to want the matching batteries to charge safely, presumably with a low enough internal resistance and a charge characteristic matched to the charger...

So is your problem that the charger seems to not like regular rechargeables, or that the camera does not like the rechargeables you may have got with the charger?

The charger is supposed to charge NiMh AA batteries in the range 1700-2500 mAh. The ones in question are 2000mAh and of the same make as the charger.

If I charge batteries the camera will reject them.
If I insert already charged batteries back in the charger, the charger will reject them as "reversed polarity"
Both the camera and the charger are rejecting the charged batteries.

Curious. You say the batteries work okay in a torch. If you have a multimeter of some sort I suppose it would be worth seeing if the reverse polarity warning is true, though I can't see how that could happen as the poles of the battery contain different materials. If you don't have a multimeter, take a regular nonrechargeable battery and one of your rechargeables and put these in a two-cell torch facing the way they are meant to go. If the rechargeable is really reverse polarity then it will cancel out most of the voltage of the regular battery and the torch won't light properly. If so take charger back to the store as faulty, and maybe ask them to replace your rechargeables too since they were presumably good before meeting that charger!

1hr fast chargers are usually sold with batteries to go with them, and sometimes switch to a lower charge rate for non-matching types. There's no excuse for wrongly polarised batteries. Though of you you do have to ask yourself the obvious question, which is you are absolutely sure and have double checked you a putting the batteries round the right way in the charger

Though of you you do have to ask yourself the obvious question, which is you are absolutely sure and have double checked you a putting the batteries round the right way in the charger

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I described what happened, ermine. I checked everything. I did get batteries with the charger, and I also bought extra batteries. The reverse polarity light can indicate other things (eg wrong sort of battery). The batteries are the right sort.

I suspect that the charged batteries may be delivering a high voltage, enough to be detected by the camera, and also ironically by the charger that charged them. This is why they work in a torch, where the voltage doesn't matter.

It is not consistent, sometimes the charged batteries work. Other times they do not. Sod's Law dictates it is the ones that you brought with you as spares that don't.

The question I asked was: has anyone else experienced this.
If yes then please post. If not then please do not bother.

"I suspect that the charged batteries may be delivering a high voltage, enough to be detected by the camera, and also ironically by the charger that charged them. This is why they work in a torch, where the voltage doesn't matter."

No. A "torch", flashlight to me, is NOT polarity sensitive but a camera is. So your batteries could very well work in a flashlight but not in a camera if you were just considering polarity only.

Zenzero said:

The question I asked was: has anyone else experienced this.
If yes then please post. If not then please do not bother.

Click to expand...

Zenzero,

Sorry for posting this despite never experiencing quite the same . I have, however, often seen strange things happen with rechargeable AAs and their chargers. I also don't think the NiMH cells can be charged to have "too high" voltage since the disposable alkaline-AAs have even higher initial voltage - and they always work.

Does the camera accept the AA-NiMHs if you have used them in a flashlight for a few minutes? It may be just that your NiMH cells have not "broken in" properly. You could use them the first few full discharge/recharge cycles completely in your flashlight - if they do work there properly - and after that start to use them in your camera. It could also be a good idea to check the cells individually because such symptoms might well be due to a single defective cell in your set - or a poorly controlled channel in your charger. It is normal that the battery gets very hot in a rapic charger, but too high temperatures can damage the cell(s) - and they use very cheap temperature sensors in the chargers.

I use this "intelligent" charger http://www.technoline.eu/details.php?id=1326&kat=15# that charges individually and measures the true mAh:s that each cell has taken up. It shows nicely if there is a poor sample among the set. It also can refresh the "tired" batteries by repeated charge-discharge cycles. Once I tried to charge a set of new 2100mAh ReCyko-batteries, but the iCharger refused to do anything. I put them in a dumb charger, and the cells were recharged fine - as they have done with the iCharger ever since.

HTH,

Ilkka

Zenzero said:

The question I asked was: has anyone else experienced this. If yes then please post. If not then please do not bother.

Click to expand...

Most Birdforum members are friendly and helpful, and with your apparent attitude you are likely to put off those that can help you solve your problem.
My advice is to get the problem batteries checked for polarity before you advance any further; maybe you have a friend with a suitable meter.

Roger

I apologise if anyone has taken offence. Thanks for the replies.

Try asking here. It's their thing.

http://www.candlepowerforums.com/vb/forumdisplay.php?f=9